As is known, roller nets essentially comprise a screen netting having a substantially rectangular shape, a terminal edge of which is fixed on a winding roller.
The winding roller is normally housed internally of a box structure which is fixed to a side of the window or the French window on which the mosquito net is applied.
The opposite terminal edge of the screen net is fixed to a bar handle, ends of which are slidably coupled to guide profiles fixed along two opposite sides of the window.
The bar handle can be translated manually distancingly from the winding roller so as to unwind and stretch the screen net on the lie plane of the window or French window.
For the mosquito net to be operative, the bar handle generally comprises hooking means which enable it to be fixed to an profiled abutment, which is anchored to the side of the window opposite the side bearing the containing structure of the winding roller.
When the presence of the mosquito net is not required and/or the passage through the window or the French window is to be used, the bar handle can be disengaged from the respective abutting profiled element in order to enable rewinding of the screen net onto the winding roller by appropriate elastic means loaded in the previous net-winding step.
Naturally, so as to prevent the undesired passage of insects through the window or French window, in the use position thereof the mosquito net must entirely occupy the passage gap and therefore must be correctly adapted to the jamb and architrave, i.e. it must be correctly sized for the window or French window to which it is fixed.
Unfortunately, as windows or French windows can be of all shapes and sizes, the mosquito net has to be specially made with suitable dimensions for the corresponding window or French window it is destined for.
Usually the task of predisposing the mosquito net with the proper measurements for the window or French window is trusted to an expert who adapts the net as required during the mounting step.
On the one hand this leads to higher costs because of the need to call an expert to adapt the mosquito net to the dimensions of the window it is destined for.
With the aim of reducing these drawbacks the industry of the sector produces mosquito nets of various standard sizes, so as to be ready for fixing.
However, the various dimensions available can cover all the really necessary sizes, especially in old buildings in which the measurements of the windows are not unified.
There are also the logistical and storage complications due to the different sizes of a same mosquito net model that have to be stored.